Publications

Ding, G 2007, 'Contaminated land' in Best, R & de Valence, G (eds), Design and Construction, Butterworth Heinemann, Oxford, pp. 195-210.
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Editorial comment One of the undesirable legacies of the industrial development of the past two centuries is the large amount of prime real estate in cities around the world that has been badly contaminated by industrial activity. In the years of uncontrolled expansion of industry in cities such as London and Manchester, great areas of land, often in what are now highly prized inner city or waterfront locations, were given over to all manner of factories and industrial plant: tanneries, refineries, power stations, forges, mills and foundries. Environmental controls were generally non-existent, chimneys belched thick smoke into the atmosphere, leaks and spills were allowed to simply soak away, all sorts of oils and solvents and toxic chemicals found their way into the soil and by leaching made their way into neighbouring sites, and all manner of human and industrial waste was discharged into local waterways. So bad was the situation that Engels, in 1844, described the River Irk in Manchester as ‘… a narrow, coal black, foul smelling stream full of debris and refuse… disgusting, blackish green slime pools… giving off a stench unendurable…’ (cited in McLaren, 1983), and the average age of death around that time amongst the working classes in London was only 22, in Leeds 21, and in Manchester, an incredible 18 (Dodds, 1953, cited in McLaren, 1983).

Indraratna, B, Fatahi, B & Khabbaz, H 2007, 'Finite element modelling of soil-vegetation interaction' in Schanz, T (ed), Theoretical and Numerical Unsaturated Soil Mechanics, SPRINGER-VERLAG BERLIN, Germany, pp. 211-223.
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Behaviour of soils in the vadose zone is closely linked to water balance between ground and atmosphere. It seems that transpiration is the most uncertain and difficult to evaluate of all the terms in the soil water balance. The key variable to estimate the transpiration rate is the rate of root water uptake, which depends on the hydrological, geological and meteorological conditions. A mathematical model for the rate of root water uptake incorporating the root growth rate, ground conditions, type of vegetation and climatic parameters, has been developed. A conical shape is considered to represent the geometry of the tree root zone. Using this proposed model, the distribution of moisture and the matric suction profile adjacent to the tree are numerically analysed. Field measurements taken from literature published previously are compared with the authorsâ numerical model. The predicted results obtained from the numerical analysis, compared favourably with the field measurements, justifying the assumptions upon which the model was developed. The analysis also indicates that soil suction and settlement increase over the time, with the effect being more significant in the first stages of transpiration.

Langston, C & Ding, G 2007, 'Sustainability and environmental assessment' in Best, R, Langston, C & de Valence, G (eds), Workplace Strategies and Facilities Management, Butterworth Heinemann, Oxford, pp. 337-351.
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Editorial comment Taking a whole-of-life approach to the management of facilities is not only an obvious strategy, but an increasingly necessary one. Built facilities have life cycles in excess of several decades, and in some cases, several centuries. It is no longer plausible to ignore future implications of present decisions and yet there is still plenty of evidence that this practice continues. If market forces do not dictate different actions then surely legislative controls will be introduced to ensure that society’s resources are used more wisely.

Choi, FC, Li, J, Samali, B & Crews, K 2007, 'An experimental study on damage detection of structures using a timber beam', Journal of Mechanical Science and Technology, vol. 21, no. 6, pp. 903-907.
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Using vibration methods for the damage detection and structural health monitoring in bridge structures is rapidly developing. However, very little work has so far been reported on timber bridges. This paper intends to address such shortcomings by experim

Choi, FC, Li, J, Samali, B & Crews, K 2007, 'Application of modal-based damage-detection method to locate and evaluate damage in timber beams', Journal of Wood Science, vol. 53, no. 5, pp. 394-400.
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Modal-based damage-detection algorithms were used to identify the location of defects commonly found in timber and to estimate their severities. In this study, the authors propose modifications to an existing damage-detection algorithm for locating and e

Choudhury, D & Nimbalkar, S 2007, 'Seismic rotational displacement of gravity walls by pseudo-dynamic method: Passive case', Soil Dynamics and Earthquake Engineering, vol. 27, no. 3, pp. 242-249.
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Prediction of the seismic rotational displacements of retaining wall under passive condition is an important aspect of design in earthquake prone region. In this paper, the pseudo-dynamic method is used to compute the rotational displacements of rigid retaining wall supporting cohesionless backfill under seismic loading for the passive earth pressure condition. The proposed method considers time, phase difference and effect of amplification in shear and primary waves propagating through both the backfill and the retaining wall. The influence of ground motion characteristics on rotational displacement of the wall is evaluated. Also the effects of variation of parameters like wall friction angle, soil friction angle, amplification factor, shear wave velocity, primary wave velocity, period of lateral shaking, horizontal and vertical seismic accelerations on the rotational displacements are studied. The rotational displacement of the wall increases substantially with increase in amplification of both shear and primary waves, time of input motion, period of lateral shaking and decreases with increase in soil friction angle, wall friction angle. The rotational displacements of the wall also increase when the effect of wall inertia is taken into account. Results are provided in graphical form. © 2006 Elsevier Ltd. All rights reserved.

Choudhury, D & Nimbalkar, S 2007, 'Seismic rotational displacement of gravity walls by pseudo-dynamic method: Passive case', SOIL DYNAMICS AND EARTHQUAKE ENGINEERING, vol. 27, no. 3, pp. 242-249.
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Choudhury, D, Nimbalkar, SS & Mandal, JN 2007, 'External stability of reinforced soil walls under seismic conditions', Geosynthetics International, vol. 14, no. 4, pp. 211-218.
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Determination of the external stability of reinforced soil walls under earthquake condition is an important topic of research for geotechnical engineers. In the present paper, a pseudo-dynamic method, which considers the effect of phase difference in both the shear and primary waves travelling through the backfill due to seismic excitation, is considered to obtain the minimum length of the geosynthetic reinforcement to resist direct sliding and overturning failure of the reinforced soil wall. A two-part wedge mechanism is used for determining the external stability of the reinforced soil wall against direct sliding. Reinforced soil walls with cohesionless backfill soil are considered in the present analysis. Results are presented in both graphical and tabular form to show the required length of the geosynthetic reinforcement to maintain the external stability of the reinforced soil wall under seismic conditions. The effects of variation of parameters such as soil friction angle, horizontal and vertical seismic accelerations on the external stability of the reinforced soil wall have been studied. With increase of seismic accelerations in both the horizontal and vertical directions, the external stability of the reinforced soil wall decreases significantly and a greater length of geosynthetic reinforcement is needed to maintain the external stability of the wall. For most practical cases, the minimum length required to resist direct sliding failure is found to govern the design rather than overturning failure under seismic conditions. Comparisons of the present results with available pseudo-static results found in the literature are shown, and the improvements using the proposed pseudo-dynamic approach are highlighted.

Connan, H, Ray, A, Thomas, P & Guerbois, J-P 2007, 'Effect of autoclaving temperature on calcium silicate-based building products containing clay-brick waste', Journal of Thermal Analysis and Calorimetry, vol. 88, no. 1, pp. 115-119.
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The utilisation of fired clay-brick waste is of interest in the manufacture of building products due to both socio-economic and technological reasons. Autoclaving is an established process for manufacturing calcium silicate-based building products that affords rapid strength development. Clay-brick waste represents a source of alternative silica, whcih is more reactive than conventionally used silica and also cntains alumina. This paper presents data on the effect of lowering the autoclaving temperature from commonly practised 180 to 170 degrees C on OPC-quartz blends conatining clay-brick fines as direct replacement of quartz at 4.3, 8.6 and 12.9 mass percentages. The hydration products of autoclaved OPC-quartz blends with clay-brick fines were characterised using simultaneous DTA-TG inc ombination with other methods.

Connan, H, Ray, AS & Thomas, PS 2007, 'Autoclaved lime-colloidal silica slurries and formation of Al-tobermorite', Journal of the Australian Ceramic Society, vol. 43, no. 2, pp. 150-153.
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Fired clay-brick waste has been the focus of research for utilisation in the hydrothermally treated CaO-Al2O3- SiO2-H2O system. Autoclaved lime-colloidal silica slurries with increasing additions of mullite, the main aluminous source in fired clay-brick were investigated. The effects of the reactivity of this alumina source on the formation and nature of Al-tobermorite were studied from a combination of solid-state 27Al MAS NMR, XRD, DTA-TGA and SEM.

Darestani, MY, Thambiratnam, DP, Nataatmadja, A & Baweja, D 2007, 'Structural response of concrete pavements under moving truck loads', JOURNAL OF TRANSPORTATION ENGINEERING-ASCE, vol. 133, no. 12, pp. 670-676.
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Ding, GKC 2007, 'Life cycle energy assessment of Australian secondary schools', Building Research & Information, vol. 35, no. 5, pp. 487-500.
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The Australian Department of Commerce builds many secondary schools in New South Wales every year, and the impact of energy consumption for such a type of construction has rarely been done before in Australia. Although there is a particular responsibility to ensure that public-owned projects contribute to the future well-being of the natural environment, environmental performance and energy efficiency of public projects are not well studied. In order that more informed design and planning decisions can be made about the future construction of school projects, this research paper uses life cycle energy analysis to study the total energy consumption of 20 public secondary school projects in New South Wales. The results will serve as a model for a more comprehensive analysis of energy consumption in establishing environmental performance criteria for the design and construction of future school projects in New South Wales.

Fatahi, B, Indraratna, B & Khabbaz, H 2007, 'Soft soil improvement induced by tree root suction', Australian Geomechanics Journal, vol. 42, no. 4, pp. 13-18.
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Bioengineering aspects of native vegetation are currently being evolved to improve soil stiffness, slope stabilisation, and erosion control. Tree roots provide three stabilising functions: (a) reinforcement of the soil, (b) dissipation of excess pore pressures and (c) establishing sufficient matric suction to increase the shear strength. The effects of vegetation on soil matric suction, shrinkage and ground settlement are discussed in this paper. A mathematical model for the rate of root water uptake that considers ground conditions, type of vegetation and climatic parameters has been developed. A conical shape is considered to represent the geometry of the tree root zone. Based on this proposed model, the distribution of the moisture and the matric suction profile adjacent to the tree are numerically analysed. Field measurements taken from literature published previously are compared with the authors' numerical model. The predicted results, calculated based on soil, plant, and atmospheric parameters contained in the numerical model, compared favourably with the measured results, justifying the assumptions upon which the model has been developed. The findings of this study indicate that due to significant changes in soil moisture content induced by tree roots, the shear strength of the soil will be enhanced. It is desirable to consider the influence zone of tree roots and the improved soil properties in modern geotechnical designs, benefiting from native vegetation.

Hong, S, Nguyen, M, Kwok, N, Ha, QP & Li, J 2007, 'Hysteretic model for magnetorheological fluid dampers using a curve fitting approach', Journal of JSAEM, Japanese Society of Applied Electromagnetics and Mechanics, vol. 15, pp. 176-179.

Indraratna, B, Raut, AK & Khabbaz, H 2007, 'Constriction-based retention criterion for granular filter design', JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING, vol. 133, no. 3, pp. 266-276.
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The filter design criteria in practice are currently based on laboratory tests that were carried out on uniform base soil and filter materials. These criteria mostly involve specific particle size ratios, where the system of base soil and filter is represented by some characteristic particle sizes. Consequently, these criteria have limitations when applied to nonuniform materials. In filters, it is the constriction size rather than the particle size that affects filtration. In this paper, a mathematical procedure to determine the controlling constriction size is introduced, and subsequently, a constriction-based retention criterion for granular filters is presented. The model also incorporates the effect of nonuniformity of base soil in terms of its particle size distribution, considering the surface area of the particles. The proposed retention criterion is verified based on experimental data taken from past studies plus large-scale filtration tests carried out by the authors. The model successfully and distinctly demarcates the boundary between effective and ineffective filters in the case of cohensionless base soils. © 2007 ASCE.

Kwok, NM, Ha, QP, Huang, S, Dissanayake, G & Fang, G 2007, 'Mobile robot localization and mapping using a Gaussian sum filter', INTERNATIONAL JOURNAL OF CONTROL AUTOMATION AND SYSTEMS, vol. 5, no. 3, pp. 251-268.
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A Gaussian sum filter (GSF) is proposed in this paper on simultaneous localization and mapping (SLAM) for mobile robot navigation. In particular, the SLAM problem is tackled here for cases when only bearing measurements are available. Within the stochastic mapping framework using an extended Kalman filter (EKF), a Gaussian probability density function (pdf) is assumed to describe the range-and-bearing sensor noise. In the case of a bearing-only sensor, a sum of weighted Gaussians is used to represent the non-Gaussian robot-landmark range uncertainty, resulting in a bank of EKFs for estimation of the robot and landmark locations. In our approach, the Gaussian parameters are designed on the basis of minimizing the representation error. The computational complexity of the GSF is reduced by applying the sequential probability ratio test (SPRT) to remove under-performing EKFs. Extensive experimental results are included to demonstrate the effectiveness and efficiency of the proposed techniques.

Kwok, NM, Ha, QP, Nguyen, MT, Li, J & Samali, B 2007, 'Bouc-Wen model parameter identification for a MR fluid damper using computationally efficient GA', ISA TRANSACTIONS, vol. 46, no. 2, pp. 167-179.
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A non-symmetrical Bouc-Wen model is proposed in this paper for magnetorheological (MR) fluid dampers. The model considers the effect of non-symmetrical hysteresis which has not been taken into account in the original Bouc-Wen model. The model parameters are identified with a Genetic Algorithm (GA) using its flexibility in identification of complex dynamics. The computational efficiency of the proposed GA is improved with the absorption of the selection stage into the crossover and mutation operations. Crossover and mutation are also made adaptive to the fitness values such that their probabilities need not be user-specified. Instead of using a sufficiently number of generations or a pre-determined fitness value, the algorithm termination criterion is formulated on the basis of a statistical hypothesis test, thus enhancing the performance of the parameter identification. Experimental test data of the damper displacement and force are used to verify the proposed approach with satisfactory parameter identification results. © 2007 ISA.

Li, J, Choi, FC, Samali, B & Crews, K 2007, 'Damage localisation and severity evaluation of a beam-like timber structure based on modal strain energy and flexibility approaches', Journal of Building Appraisal, vol. 2, no. 4, pp. 323-334.
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Liu, A, Wu, C, Yu, KF & Yuan, W 2007, 'Completeness and unbiased estimation of mean vector in the multivariate group sequential case', Journal of Multivariate Analysis, vol. 98, no. 3, pp. 505-516.
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We consider estimation after a group sequential test about a multivariate normal mean, such as a χ2 test or a sequential version of the Bonferroni procedure. We derive the density function of the sufficient statistics and show that the sample mean remains to be the maximum likelihood estimator but is no longer unbiased. We propose an alternative Rao-Blackwell type unbiased estimator. We show that the family of distributions of the sufficient statistic is not complete, and there exist infinitely many unbiased estimators of the mean vector and none has uniformly minimum variance. However, when restricted to truncation-adaptable statistics, completeness holds and the Rao-Blackwell estimator has uniformly minimum variance.

Liu, B, Ray, A, Thomas, PS, Klimesch, D & Guerbois, JP 2007, 'Mechanical properties of hydrothermally treated alumina-silica rich industrial waste cement systems - Effect of magnesia addition', Journal of Solid Waste Technology and Management, vol. 33, no. 2, pp. 61-66.
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The utilisation of industrial waste products such as fly ash, blast furnace slag and fired claybrick, as supplementary cementing materials to produce blended Portland cement (PC) has increased worldwide in recent years. The incentive was directed towards the utilisation of wastes and industrial by-products in order to minimise PC consumption, thus reduce CO2 emissions. This study aims to investigate the potential of magnesia (MgO) as a supplementary material in combination with alumina-silica rich fired clay brick waste fines. Compressive strength results showed adverse effects on the additions of brick waste fines and MgO. However, for blended PC with the addition of both brick waste and magnesia, an apparent synergy, indicating a minimising of strength reduction, was observed. X-ray diffraction (XRD) data revealed the presence of brucite, a hydration product of MgO, in the MgO blended PC suggesting a lack of pozzolanic activity of MgO.

Liu, B, Ray, AS & Thomas, PS 2007, 'Strength development in autoclaved aluminosilicate rich industrial waste-cement systems containing reactive magnesia', Journal of the Australian Ceramic Society, vol. 43, no. 1, pp. 82-87.
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Addition of supplementary cementing materials (SCM) to produce blended Portland cements (PC) is a well established practice in the manufacture of construction materials since they permit less overall consumption of PC thereby reducing CO2 emissions. This study reports findings on the strength development of autoclaved Portland cement (PC) - quartz blends where PC was partially replaced by alumina-silica rich fired clay brick waste frees, a proven SCM, and reactive magnesia. Chemical and physical properties of the mixes were characterised by means of compressive strength testing thermal analysis, x-ray diffractometry (XRD) and scanning electron microscopy (SEM).

Liu, B, Thomas, PS, Ray, AS & Guerbois, JP 2007, 'A TG analysis of the effect of calcination conditions on the properties of reactive magnesia', JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY, vol. 88, no. 1, pp. 145-149.
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The reactivity of MgO obtained from calcination of magnesium carbonate at different temperatures has been investigated by means of hydration in a constant relative humidity environment at 40 degrees C for periods up to 24 days. Natural magnesite and AR g grade basic MgCO3 calcinated in the range of 500-1000 degrees C was characterised in terms of surface area, crystallite size, morphology, and hydration rate. It was foudn that the hydration rate is dependent on the surface area and crystallite size wwhere temperature was the main variable affecting them. The most reactive MgO was produced at the lowest calcination temperature with the highest surface area and the smallest crystallite size. The basic MgO specimens showed higher degree of hydration compared to the natural mgO specimens due to the smaller surface area and larger cyrstallite size. The low MgO content of the starting natural magnesite is also attributable to the lower reactivity. This preliminary study serves as a mean to investigate poetntial utilisation of reactive MgO asa supplementary cementitious material in eco-freindly cements.

Liu, B, Thomas, PS, Ray, AS, Williams, RP & Donne, SW 2007, 'DSC characterisation of chemically reduced electrolytic manganese dioxide', JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY, vol. 88, no. 1, pp. 177-180.
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The thermal decomposition of electrolytic manganese dioxide (EMD), in an inert atmosphere, and the effect of chemical reduction on EMD, using 2-propanol under reflux (82 degrees C), was investigated by differential scanning calorimetry (DSC). This study

Nimbalkar, S & Choudhury, D 2007, 'Sliding stability and seismic design of retaining wall by pseudo-dynamic method for passive case', Soil Dynamics and Earthquake Engineering, vol. 27, no. 6, pp. 497-505.
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Onishi, A, Thomas, PS, Stuart, BH, Guerbois, JP & Forbes, S 2007, 'TG-MS characterisation of pig bone in an inert atmosphere', JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY, vol. 88, no. 2, pp. 405-409.
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A challenge for forensic examiners is the ageing and characterisation of bone fragments or decomposed skeletal remains. Due to the sensitivity of thermal methods to morphological states, thermal analysis has been selected as a technique which could overcome the difficulties. In this preliminary study, TG-MS was applied to the characterisation of bone fragments derived from the compact bone of pig rib specimens. TG-MS curves were collected by heating bone samples to 1000 degrees C in an argon atmosphere. under these conditions, both the organic and inorganic phases decomposed, producing a variety of organic fragments and carbon dioxide. Pyrolysis of the organic phase, which is composed predominantly of collagen, occurred resulting in the observation of ion fragments up to 110 amu. Selected fragments were monited and their observation is discussed in terms of the decomposition of both the collagen phase and the inorganic carbonated hydroxyapatite phase.

Ray, A, Sriravindrarajah, R, Guerbois, J-P, Thomas, PS, Border, S, Ray, HN, Haggman, J & Joyce, P 2007, 'Evaluation ofwaste perlite fines in the production of construction materials', Journal of Thermal Analysis and Calorimetry, vol. 88, no. 1, pp. 279-283.
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The use of supplementary cementitious materials (SCM) is a well established practice worldwide in the manufacture of Portland cement (PC)-based construction materials. While utilisation of industrial by-products has been successful, the potential of mining wastes is yet yo receive adequate attention in the context of construction materials. In an expanded form perlite, which is a naturally occurring, hydrated volcanic siliceous glass, is an adeal material as a lightweight aggregate for usein a wide range of construction materials including concrete. The mining and processing of the grades of perlite required for the production of lightweight aggregate results inthe cereation of a fine grained waste wjhich currently hasno economic value. This paper reports preliminary data on the utilisation of waste perlite fines as a SCM in calcium silicate-based construction material and discusses the potential of this mining waste to reduce the environmental impact of the production of conventional cement-based consturction materials.

Samali, B, Li, J, Crews, KI & Al-dawod, M 2007, 'Load rating of impaired bridges using a dynamic method', Electronic Journal of Structural Engineering, vol. 7, pp. 66-75.
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Local Government in Australia is responsible for the operational management and maintenance of over 20,000 bridges. More than 70% of these bridges comprise aging timber bridges, the load capacity and structural adequacy of many of which have been impaired over time. This is partly due to increased vehicular loads with little attention to consequence of such increases. It is now necessary to determine the load carrying capacity of these bridges using simple yet reliable methods to allow local authorities to upgrade, replace or sign post at-risk bridges. In this paper a novel dynamic based method is presented by which the in-service stiffness of the bridge is estimated first. From this stiffness the load carrying capacity of the bridge is estimated following a statistically based analysis.

Smallwood, A, Thomas, PS, Ray, AS & Simon, P 2007, 'TMA and SEM characterization of the thermal dehydration of australian sedimentary opal', JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY, vol. 88, no. 1, pp. 185-188.
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The dehydration of samples of a Coober Pedy, South Australian sedimentary white opal, displaying play of colour, was investigated using TMA by heating the samples of the specimen to a range of temperatures between room temperature and 1000 at 200 degrees

Thomas, PS, Simon, P, Smallwood, A & Ray, AS 2007, 'Estimation of the diffusion coefficient of water evolved during the non-isothermal dehydration of Australian sedimentary opal', JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY, vol. 88, no. 1, pp. 231-235.
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The dehydration of an opal specimen was investigated by thermogravimetric analysis (TG) in powder and bulk forms. The change in geometry resulted in a significant difference in the temperature range in which dehydration occurred with peak temperatures in the differential TG (DTG) curve for the hand ground opal at 203 degrees Cand for the bulk opal at 340 degrees C. This difference waa attributed to time taken for diffusion of feree water in the bulk opal tothe specimen surface prior to evolution as a registered mass loss. A model was proposed to account for the diffusion of water and was used to estimate the diffusion coefficient.

Trinh, H & Ha, QP 2007, 'State and input simultaneous estimation for a class of time-delay systems with uncertainties', IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS II-EXPRESS BRIEFS, vol. 54, no. 6, pp. 527-531.
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This brief addresses the problem of estimation of both the states and the unknown inputs of a class of systems that are subject to a time-varying delay in their state variables, to an unknown input, and also to an additive uncertain, nonlinear disturbance. Conditions are derived for the solvability of the design matrices of a reduced-order observer for state and input estimation, and for the stability of its dynamics. To improve computational efficiency, a delay-dependent asymptotic stability condition is then developed using the linear matrix inequality formulation. A design procedure is proposed and illustrated by a numerical example. © 2007, IEEE. All rights reserved.

Wang, JG & Wang, J 2007, 'Adaptive Tropospheric Delay Modelling in GPS/INS/Pseudolite Integration for Airborne Surveying', Journal of Global Positioning Systems, vol. 6, no. 2, pp. 142-148.
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Integrated GPS/INS systems have been used for geo-referencing airborne surveying and mapping platforms. However, due to the limited constellation of GPS satellites and their geometric distribution, the accuracy of such integraed systems cannot meet the requirements of precise airborne surveying. This problem can be addressed by including additional GPS-like ranging signals transmitted from the ground-based pseudolites (PLs). As GPS measurement geometry can be strengthened dramatically by the PL augmentation, systems accuracy and reliability can be improved, especially in the vertical component. Nevertheless, some challenges exist for PLs augmentation. As PLs are relatively close to the receivers, the unit vectors from a PL to reference and rover receivers can be significantly different. PL tropospheric delay modelling errors cannot be effectively mitigated in differencing procedure. Furthermore, PL signals propagate through the lower troposphere, where it is very difficult to accurately model the signal delay due to temporal and spatial variations of meteorological parameters. An adaptive PL tropospheric delay modelling method is developed to reduce modelling error by estimating meteorological parameters in a model. The performance of this method is evaluated with field test data. The testing has shown that the PL tropospheric delay modelling error can be effectively mitigated by the proposed method.

White, R, Thomas, PS, Philips, MR, Wuhrer, R & Guerbois, JP 2007, 'TG-MS characterization of the reaction products of cadmium yellow and malachite artist's pigments', JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY, vol. 88, no. 1, pp. 181-184.
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The deleterious interaction of some traditional sulphide artists pigments and copper ions results in the formation of black copper sulphides, in particular, covellite (CuS), and, hence, the discolouration of valuable artworks. In this paper the interaction of malachite, a source of copper(II) ions, with the pigment cadmium yellow, a sulphide pigment comprising of a solid solution of cadmium and zinc sulphides, is investigated by XRD and TG-MS. XRD showed the presence of the copper sulphide and cadmium carbonate phases, produced by a simple ion exchange mechanism. TG-MS showed the complexity of the range of metastable phases produced. The identification of these phases, however, requires further work. © Springer-Verlag 2007.

Widjaja, J, Samali, B & Li, J 2007, 'Erratum: The use of displacement threshold for switching frequency strategy for structural vibration mitigation (Journal of Mechanical Science and Technology (2007) 21 (865-869))', Journal of Mechanical Science and Technology, vol. 21, no. 10, p. 1756.
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Widjaja, J, Samali, B & Li, J 2007, 'The use of displacement threshold for switching frequency strategy for structural vibration mitigation', Journal of Mechanical Science and Technology, vol. 21, no. 6, pp. 865-869.
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Wu, C & Hao, H 2007, 'Numerical simulation of structural response and damage to simultaneous ground shock and airblast loads', International Journal of Impact Engineering, vol. 34, no. 3, pp. 556-572.
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Wu, C & Hao, H 2007, 'Safe Scaled Distance for Masonry Infilled RC Frame Structures Subjected to Airblast Loads', Journal of Performance of Constructed Facilities, vol. 21, no. 6, pp. 422-431.
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Wu, C & Liu, A 2007, 'An adaptive approach for bivariate phase II clinical trial designs', Contemporary Clinical Trials, vol. 28, no. 4, pp. 482-486.
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In designing a phase II cancer clinical trial monitoring simultaneously the response and toxicity rate of a therapeutic agent, the odds ratio has to be specified. The false positive or Type I error rate, however, can be substantially inflated if the specified value is considerably larger than the true odds ratio. To overcome the sensitivity of the error rates to the odds ratio, an adaptive procedure is proposed which allows the sample size to be re-estimated based on observed odds ratio. Simulation results show that the procedure is robust against the odds ratio assumptions and controls effectively the Type I error rate. © 2007 Elsevier Inc. All rights reserved.

Wu, C, Liu, A & Yu, KF 2007, 'An Adaptive Approach to Designing Comparative Diagnostic Accuracy Studies', Journal of Biopharmaceutical Statistics, vol. 18, no. 1, pp. 116-125.
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Comparative diagnostic studies usually involve comparison of the area under receiver operating characteristic curves when biomarkers are measured on a continuous or ordinal scales. In designing such studies, specification of a number of nuisance parameters is often required to compute sample sizes. When these parameters are incorrectly specified, statistical power to detect a meaningful difference in area can be substantially adversely affected. We propose an adaptive method to calculate the sample size and show these procedures to be effective in controlling error rates. Copyright © Taylor & Francis Group, LLC.

Wu, C, Oehlers, DJ, Wachl, J, Glynn, C, Spencer, A, Merrigan, M & Day, I 2007, 'Blast Testing of RC Slabs Retrofitted with NSM CFRP Plates', Advances in Structural Engineering, vol. 10, no. 4, pp. 397-414.
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In this paper, blast testing was performed on two reinforced concrete specimens: a plain reinforced concrete (RC) specimen; and an identical RC specimen retrofitted with near surface mounted (NSM) carbon fibre reinforced polymer (CFRP) plates. Each specimen was subjected to two separate explosive loads at a standoff distance of 0.6m, with the aim of investigating the performances of both specimens within both their elastic and plastic response ranges. The first blast (Blast 1) and second blast (Blast 2) consisted of an equivalent TNT charge weight of 0.079kg and 2.09kg respectively. The elastic-range responses of both specimens after the small shot (Blast 1), such as acceleration and deflection were obtained and comparisons were made between the specimens. The plastic performances of both specimens, such as tension face scabbing, crack patterns, plastic hinges and permanent deflection, after the large shot (Blast 2) were also analysed and compared. A number of unique failures and behaviours of both specimens were observed, investigated and analyzed. The test results provide a vital direction in the development of an optimal retrofit in future research.

Wu, CQ, Sun, WB & John, OD 2007, 'Optimal design of RC panels against blast loads using energy-based approach', Jiefangjun Ligong Daxue Xuebao/Journal of PLA University of Science and Technology (Natural Science Edition), vol. 8, no. 6, pp. 645-651.
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Displacement-controlled approach is now being used by current guidelines such as TM5 and ASCE to design RC structures against blast loads. Although this method is easy to use, it may not obtain an optimal design. Actually the area under the resistance-deflection curve of a RC member represents its energy-absorption and thus a slab with different reinforcement ratios absorbs energy differently. The optimal reinforcement ratio for a slab corresponds to its maximum energy absorption capacity. A layered analytical model which allows for the varying strain rates over the cross-section was used to calculate a bilinear resistance-deflection relationship for a simply supported slab with different ratios so that the maximum energy absorption capacity of the slab as well as its optimal reinforcement ratio could be determined. Geometric size of the slab on the influence of the optimal reinforcement ratio was also investigated. The developed method is very useful to facilitate an optimal design to resist air-blast loads.

Choi, FC, Li, J, Samali, B & Crews, K 1970, 'Damage evaluation of a timber beam using a modal-based method', Progress in Mechanics of Structures and Materials - Proceedings of the 19th Australasian Conference on the Mechanics of Structures and Materials, ACMSM19, Australasian Conference on the Mechanics of Structures and Materials, Taylor and Francis, Christchurch, New Zealand, pp. 1005-1010.
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In Australia, many timber bridges are old and increasingly experience deterioration, aging and traffic overloading problems. These have attracted attention of researchers to evaluate the current state of such bridges. Whilst proof-load testing and traditional nondestructive evaluation (NDE) provide valuable tools, such procedures are often time consuming and costly. For bridge structures, to develop effective NDE at global level viz damage identification and structural health monitoring using modal-based damage identification methods have engrossed recent worldwide research efforts. However, to date there are few works reported on timber bridges using modal-based damage identification methods to evaluate their state of health. In this paper, modal-based damage identification methods for localization of damage in timber bridges are presented based on finite element analysis (FEA) and test results of a timber beam. Two algorithms of global NDE for identifying local damage and decay in timber structures are investigated. The methods employ modal parameters that monitor changes in modal strain energy (MSE) based on curvature mode shapes of a damaged beam with respect to the undamaged one. The aim of the study is to investigate the capability and limitations of the proposed algorithms for detecting damage with multiple damage scenarios in timber structures. Between the two proposed modal based damage identification algorithms, the modified method has shown better results in solving multiple damage problems. © 2007 Taylor & Francis Group, London.

Crews, K 1970, 'Defining appropriate limit states for design of timber connections in Australia and New Zealand', Progress in Mechanics of Structures and Materials - Proceedings of the 19th Australasian Conference on the Mechanics of Structures and Materials, ACMSM19, Australasian Conference on the Mechanics of Structures and Materials, Taylor & Francis (Balkema), Christchurch, New Zealand, pp. 1011-1016.
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Both Australia and New Zealand design standards for timber structures are in limit states format, but these are first generation soft conversions of previous working stress design standards. It is anticipated that development of a new combined Australian and New Zealand standard for design of timber structures will commence shortly. There is a shared view amongst some researchers that the current approach is limited, since it does not distinguish between serviceability and 'ultimate' strength events and is not particularly relevant for connections in high performance timber structures. This paper discusses these matters and presents an overview of relevant literature and research work that has been undertaken to date, with recommendations for future development. © 2007 Taylor & Francis Group, London.

Ding, GK, Smith, PV & Yan, L 1970, 'The cost management system in China - The impact of social and economic reforms in the construction industry', Proceedings of CRIOCM 2007 International Research Symposium on Advancement of Construction Management and Real Estate, Construction Management and Real Estate International Symposium, The Chinese Research Institute of Construction Management, Sydney, pp. 660-669.

Ding, GKC 1970, 'The evaluation of environmentally sustainable residential development using a building sustainability index', Association of Researchers in Construction Management, ARCOM 2007 - Proceedings of the 23rd Annual Conference, Association of Researchers in Construction Management Annual Conference, ARCOM Association of Researchers in Construction Management, Belfast, Northern Ireland, UK, pp. 851-860.
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Green homes or eco-homes have been built in many countries and have played an important role in setting a benchmark in ecologically sensitive housing and guiding industry in the design and construction of sustainable houses. According to the Department of Infrastructure, Planning and Natural Resources a new dwelling is built every 14 minutes in New South Wales, Australia. This paper examines the introduction of an online tool the Building and Sustainability Index (BASIX) as mandatory to all residential developments in New South Wales. It is two and half years since the introduction of the index and yet no attempt has been made to ascertain its impact on the construction industry. An online survey was conducted to ascertain this impact and it was found that free access to the tool via internet was one of the main reasons for its success. It was also generally accepted that the tool has played a significant role in providing a general guideline for the sustainability performance of a proposed development. This paper discusses the results of the survey.

Ding, GKC & Runeson, G 1970, 'A basix tool for environmental assessment of residential buildings - An australian approach', CME 2007 Conference - Construction Management and Economics: 'Past, Present and Future', Construction Management and Economics Conference, University of Reading, UK, Reading, UK, pp. 931-939.
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The rapidly growing population in New South Wales (NSW) is the driving force behind the growth in new housing. The environmental impact in terms of land use, energy and resource consumption will significantly impede the supply of new housing. In NSW, sustainable housing has become an important focus of the government's housing policy. In response to the need for sustainable housing, the government launched a sustainability assessment tool called BASIX in July 2004 to assess and establish indoor thermal comfort, water and energy efficiency targets, and sustainability levels. The introduction of BASIX has had a profound impact on the construction industry. In order to ascertain the extent of impact, an online survey was conducted among construction professionals in NSW in March 2006. The tool has played a significant role in providing a general guideline for the sustainability performance of proposed developments. It serves as a means to make people think about water and energy saving initiatives, and to encourage good design practice without excessive additions to the cost of a new building. However, there is the opinion that there is more to be done such as control of waste and energy usage in the manufacturing of building materials.

Fatahi, B, Indraratna, B & Khabbaz, H 1970, 'Analysing Soft Ground Improvement Caused by Tree Root Suction', Advances in Measurement and Modeling of Soil Behavior, Geo-Denver 2007, American Society of Civil Engineers, Denver, Colorado, USA, pp. 6-10.
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Bioengineering aspects of native vegetation are currently being evolved to improve soil stiffness, slope stabilisation, and erosion control. Vegetation contributes to weak soil stabilisation through reinforcement of the soil, dissipation of excess pore pressures, and increasing the shear strength by induced matric suction. This paper looks at the way that vegetation influences soil matric suction, shrinkage, and ground settlement. A theoretical model previously developed by the authors for the rate of tree root water uptake together with an associated numerical simulation is used in this study. A conical shape is considered to represent the geometry of the tree root zone. Based on this proposed model, the distribution of moisture and the matric suction profile adjacent to the tree are numerically analysed. Field measurements taken from previously published literature are compared with numerical predictions for further validation. The predicted results compared favourably with the measured results, justifying the assumptions upon which the model was developed. It is desirable to consider the influence zone of tree roots and the improved soil properties in modern geotechnical designs, benefiting from native vegetation. Copyright ASCE 2007.

Fatahi, B, Indraratna, B & Khabbaz, H 1970, 'Enhanced numerical analysis of ground behaviour influenced by tree root suction', Common Ground: Proceedings of the 10th Australia and New Zealand Conference on Geomechanics, Australia New Zealand Geomechanics conference, Coffey Geotechnics, Brisbane, Australia, pp. 142-147.
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Tree roots provide three stabilising functions: (a) reinforcement of the soil, (b) dissipation of excess pore pressures, (c) establishing sufficient matric suction to increase the shear strength. This paper looks at the way that vegetation influences soil moisture content distribution, and ground settlement. A theoretical model previously developed by the authors for the rate of tree root water uptake together with an associated numerical simulation is used in this study. Field measurements taken from literature published previously are compared with the authors' numerical model. The predicted results obtained from the numerical analysis, compared favourably with the field measurements, justifying the assumptions upon which the model was developed.

Gerber, C, Crews, K & Sigrist, C 1970, 'Accessible and reliable design of stressed-skin panels - An Australian perspective', Progress in Mechanics of Structures and Materials - Proceedings of the 19th Australasian Conference on the Mechanics of Structures and Materials, ACMSM19, Australasian Conference on the Mechanics of Structures and Materials, Taylor & Francis (Balkema), Christchurch, New Zealand, pp. 1017-1022.
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Stressed-skin panel (SSP) technology possesses many advantages and the subject research program has increased the understanding of SSP structures with respect to serviceability and ultimate resistance performance. In order for the building industry to capitalise on the results of this research, it is essential that the codes i.e. AS 1720.1-1997 (Australian Standard™ 1997) should embrace a design procedure enabling the use of the full potential of SSP systems. This paper outlines an amendment proposal to Section 5 of AS 1720.1-1997 that will enable designers to achieve a problem-free and efficient implementation of SSP technology. It focuses on the aspects of the tributary width of the sheathing and the stress determinations in the composite section. The proposed design procedure is both useable and straightforward to implement and satisfies requirements of structural safety and comfortable serviceability. It is based on a solid research background and relates to EC5 (European Committee for Standardisation 1995), which will necessitate some adjustments to fully comply with Australian design standard. © 2007 Taylor & Francis Group, London.

Gerber, C, Crews, K & Sigrist, C 1970, 'Screw- and nail-gluing techniques for wood composite structures', Progress in Mechanics of Structures and Materials - Proceedings of the 19th Australasian Conference on the Mechanics of Structures and Materials, ACMSM19, Australasian Conference on the Mechanics of Structures and Materials, Taylor & Francis (Balkema), Christchurch, New Zealand, pp. 1023-1029.
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Composite systems enhance the structural capacity and reliability of wood solutions for structures. With today engineered wood products and structural adhesives, high performing structures can be constructed. Hybrid assembly techniques that combine mechanical fasteners and an adhesive (screw- and nailgluing techniques) allow manufacturing large dimension composite structures with reasonable infrastructure. They also give full composite properties to the interlayers. Furthermore, these hybrid connections can experience ductility. This paper presents a research on small-scale glued assemblies which were manufactured using screw- and nail-gluing techniques. It discusses qualitative and quantitative analyses that confirmed the full-composite properties and ductility of the interlayers. The analyses also show that superposing the behaviour of both connectors is reasonable to predict the strength and slip modulus of hybrid connections. © 2007 Taylor & Francis Group, London.

Haskett, M, Oehlers, D & Wu, C 1970, 'Comparison of the interfacial bond and slip behaviour of steel and FRP reinforcement', Proceedings of the 1st Asia-Pacific Conference on FRP in Structures, APFIS 2007, pp. 731-737.
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Ductility of FRP plated reinforced concrete (RC) structures is essential to provide structural members with the ability to sustain deformation without the subsequent loss of strength prior to collapse. Often this is achieved in RC structures by prescribing the sections to be under-reinforced, and dictated by the neutral axis factor ku, which assumes a concrete crushing type failure. In FRP plated structures, often concrete crushing does not occur and instead the plates fracture or debond prior to this occurring. As such the ductility of plated structures is much more difficult to quantify in terms of a dimensionless property, such as the neutral axis factor ku. This paper reports on the development of a local bond-stress slip (τ−δ) relationship for steel reinforcing bars that has been attained independent of embedment length. Subsequently the use of this relationship in a numerical simulation package compares the behaviour of steel and FRP reinforcing bars to failure, indicating the influence of yielding on the global load-slip (P−Δ) response.

Ip, K, Thomas, P, Stuart, BH & Ray, AS 1970, 'Thermal characterisation of the clay binder of heritage Sydney sandstone', Medicta 2007: The 8th Mediterranean Conference on Calorimetry and Thermal Analysis Book of Abstracts, 8th Mediterranean Conference on Calorimetry and Thermal Analysis, Palermo.

Kwok, N, Carmichael, MG, Ha, QP & Tan, K 1970, 'Statistical decision based gray-level image feature matching', Proceedings of the 8th International Conference on Intelligent Technologies (InTech'07), International Conference on Intelligent Technologies, University of Technology Sydney, Sydney, Australia, pp. 269-274.
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Na

Kwok, NM, Ha, QP & Samali, B 1970, 'MR Damper Optimal Placement for Semi-Active Control of Buildings Using an Efficient Multiobjective Binary Genetic Algorithm', Automation and Robotics in Construction ― Proceedings of the 24th International Symposium on Automation and Robotics in Construction, 24th International Symposium on Automation and Robotics in Construction, International Association for Automation and Robotics in Construction (IAARC), Kochi, pp. 361-367.
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In order to ensure the survival of building structures during earthquake periods, induced vibrations have to be mitigated. In this regard, semi-active control of smart structures using magneto-rheological dampers is becoming an emerging technology. Improvements on vibration reduction are foreshadowed when the dampers are installed at critical locations on the building structure. In this paper, the placement of dampers is cast as a multi-objective optimization problem in the sense of minimum resultant vibration magnitudes and with a minimum number of dampers. A binary-coded genetic algorithm is employed as the optimizer owing to its computational flexibility and high performance. Simulation results are included to illustrate the effectiveness of the proposed approach on a high-rise building model subject to benchmark earthquake records.

Li, J, Choi, FC & Samali, B 1970, 'Modal-based damage identification methods for plate-like structures', Progress in Mechanics of Structures and Materials - Proceedings of the 19th Australasian Conference on the Mechanics of Structures and Materials, ACMSM19, Australasian Conference on the Mechanics of Structures and Materials, Taylor and Francis, Christchurch, New Zealand, pp. 909-914.
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A great deal of work has been done in the area of damage identification in structures using changes of modal parameters before and after damage. Most of the developments have been based on beam theory and application to beam-like or truss structures. Few researchers have contributed to in-depth study of damage identification of plate-like structures employing modal-based methods. In this paper, two modal strain energy based damage identification methods have been expanded for detecting damage and evaluation of damage severity in plate-like structures. The study is based on finite element analysis (FEA) results of a plate model. The purpose of the study is to explore feasibility of using modal strain energy based methods for damage identification of plate-like structures. The results show that one modified method based on a two-dimensional mode shape curvature in computing the damage index provides very good damage localisation and severity estimation. © 2007 Taylor & Francis Group, London.

Li, J, Samali, B & Crews, K 1970, 'A cost effective approach for integrity assessment of timber bridges', Progress in Mechanics of Structures and Materials - Proceedings of the 19th Australasian Conference on the Mechanics of Structures and Materials, ACMSM19, Australasian Conference on the Mechanics of Structures and Materials, Taylor and Francis, Christchurch, New Zealand, pp. 1037-1042.
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To develop a reliable and cost effective tool to assess the structural integrity of aged timber bridges is currently a challenge facing structural engineers. Whilst proof-load testing and Non-destructive Evaluation (NDE) techniques provide valuable assessment, such procedures are generally too complex, costly and time consuming to be applied across the entire inventory of timber bridges. A simple dynamic based testing method was developed by authors to lower the cost and shorten the testing time. The method has recently been used successfully to undertake field-testing of more than 180 timber bridges across NSW. This paper summarises the analytical development of this new approach together with some experimental examples. In the analytical studies, a closed form solution was obtained to provide an explicit relationship between the flexural stiffness and measured modal parameters. A beam with spring and masses attached was used to model a bridge with added mass or alternative added mass such as a trailer and/or a water tank for bridge testing. After obtaining the in-service stiffness of the tested bridge, a probabilistic modelling based on bending strength and gross stiffness (EI) of timber girders, is developed to provide an assessment of bridge load carrying capacity by using predicted in-service stiffness. Results of experimental studies and field testing using this approach are given in the references. © 2007 Taylor & Francis Group, London.

Li, Y, Wang, J & Qian, L 1970, 'A new methodology of modeling a novel large-scale magnetorheological impact damper', Nonlinear Science and Complexity, Conference on Nonlinear Science and Complexity, WORLD SCIENTIFIC PUBL CO PTE LTD, Beijing, PEOPLES R CHINA, pp. 382-387.
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Li, Y, Wang, J & Qian, L 1970, 'Nonlinear characteristics of magnetorheological damper under base excitation', Nonlinear Science and Complexity, Conference on Nonlinear Science and Complexity, WORLD SCIENTIFIC PUBL CO PTE LTD, Beijing, PEOPLES R CHINA, pp. 388-393.
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Nguyen, M, Kwok, N, Ha, QP, Li, J & Samali, B 1970, 'Mitigation of Seismic Responses in Building Structures using Magneto-rheological Dampers', Proceedings of the 24th International Symposium on Automation and Robotics in Construction (ISARC 2007), International Symposium of Automation and Robotics in Construction, Indian Institute of Technology Madras, Kochi, Kerala, India.

Nguyen, MT, Kwok, NM, Ha, QP, Li, J & Samali, B 1970, 'Semi-active direct control of civil structure seismic responses using magneto-rheological dampers', Automation and Robotics in Construction - Proceedings of the 24th International Symposium on Automation and Robotics in Construction, International Symposium on Automation and Robotics in Construction, Lokavani Southern Printers, Kochi, India, pp. 157-162.
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As building structures frequently collapse and cause losses of lives and properties, due to excessive vibrations induced during earthquake periods, it is crucial to reduce the structural vibrations. This paper develops a Lyapunov-based controller for Magnetorheological (MR) dampers embedded in building structures to mitigate quake-induced vibrations. In this work, MR dampers are used as semi-active devices, taking the advantages of the fail-safe operation and low power requirement. To enhance the system performance, a Lyapunov-based controller is proposed here for direct control of the supply currents of the MR dampers placed in a multi-storey building. The effectiveness of the proposed technique is verified in simulation by using a ten-storey building model subject to quake-like excitations.

Onishi, A, Thomas, P, Stuart, BH, Guerbois, JL & Forbes, SL 1970, 'TGMS analysis of the thermal decomposition of pig bone for forensic applications', Medicta 2007: The 8th Mediterranean Conference on Calorimetry and Thermal Analysis, 8th Mediterranean Conference on Calorimetry and Thermal Analysis, Palermo.

Saleh, A & Mok, L 1970, 'Four Point Bending Tests on rack Upright Frames with Two Different Support Conditions', Proceedings of the 6th International Conference on Steel and Aluminium Structures, 6th International Conference on Steel and Structural Engineering, Thomas Telford Ltd, Oxford, United Kingdom, pp. 1-8.
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Upright frames are a primary structural component in industrial racking systems. They are typically composed of two perforated thin-walled members that are linked together by a bracing system. Design computations in accordance with current industry standards rely in part on laboratory testing. One of these tests is for determining the bending strength of an upright section and is the subject of this paper. When testing the bending strength about the major axis of the upright, a four-point bending test of the assembled upright frame is made. The test arrangement prescribed by the standard must permit free twisting of the section at the supports, while the applied loads and their reactions for each upright may be applied in the plane of the sectionâs shear centre. Laboratory testing of two sets of upright frames, loaded through the uprightâs shear centre but with each set having a different support condition indicated that free twisting at the supports had only little influence on the bending capacity of the upright member. This paper outlines the test setup and reports the results in form of characteristic load deformation curves of the tested specimen.

Samali, B, Choi, F, Li, J & Crews, KI 1970, 'Experimental investigations on a laboratory timber bridge using Damage Index Method for plate-like structures', Proceedings of the 5th Australasian Congress on Applied Mechanics, ACAM 2007, Australasian Congress on Applied Mechanics, Engineers Australia, Brisbane, Australia, pp. 114-119.
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A great deal of work has been done in the area of damage identification in structures using changes of modal parameters before and after damage. Most of the developments have been based on beam theory and applied to beam-like or truss structures. Few researchers have made contributions to damage identification of plate-like structures employing a damage index method, especially for timber structures. In this paper, experimental investigations on a laboratory timber bridge using damage index method for plate-like structures are reported. Experimental modal analysis was performed to extract essential modal parameters from test data. Mode shape curvatures derived from the mode shapes were utilised in a damage index method for plate-like structures to detect single and two damage scenarios in a timber bridge. The purpose of the study is to explore feasibility of using modal strain energy based methods for damage identification of plate-like structures. The results show that the damage index method for plate-like structures using higher modes provides reasonable damage localisation for single and multiple damage cases.

Tran, TH, Kwok, NM, Scheding, S & Ha, QP 1970, 'Dynamic Modelling of Wheel-Terrain Interaction of a UGV', 2007 IEEE International Conference on Automation Science and Engineering, 2007 IEEE International Conference on Automation Science and Engineering, IEEE, Scottsdale, Arizona, U.S.A., pp. 369-374.
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Understanding the vehicle-terrain interaction is essential for autonomous and safe operations of skid-steering unmanned ground vehicles (UGVs). This paper presents a comprehensive analysis of the dynamic processes involved in this interaction, using the vehicle kinetics and the theory of terramechanics to derive systematically shear displacement, reaction force, and load distribution for a wheel. The new model is then summarized in the form of an algorithm to allow for computation of characteristic performance of the interaction such as slip ratios, rolling resistance, and moment of turning resistance for a number of terrain types. Given the current state of the vehicle and terrain parameters, the model can be used to estimate its next states and to predict the vehicle running path. The development is illustrated by simulation and verified with experimental data.

Widjaja, J, Samali, B & Li, J 1970, 'The use of displacement threshold for switching frequency strategy for structural vibration mitigation', JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY, 8th International Conference on Motion and Vibration Control, KOREAN SOC MECHANICAL ENGINEERS, Daejeon, SOUTH KOREA, pp. 865-869.
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Wu, C & Oehiers, DJ 1970, 'Parametric studies of RC slabs retrofitted with FRP to resist airblast loads', PROCEEDINGS OF THE 7TH INTERNATIONAL CONFERENCE ON SHOCK & IMPACT LOADS ON STRUCTURES, 7th International Conference on Shock and Impact Loans on Structures, CI-PREMIER PTE LTD, Beijing, PEOPLES R CHINA, pp. 647-653.

Wu, C, Nurwidayati, R & Ehlers, DJ 1970, 'Statistical analysis of fragment size distribution from spallation of RC slabs under airblast loads', PROCEEDINGS OF THE 7TH INTERNATIONAL CONFERENCE ON SHOCK & IMPACT LOADS ON STRUCTURES, 7th International Conference on Shock and Impact Loans on Structures, CI-PREMIER PTE LTD, Beijing, PEOPLES R CHINA, pp. 655-660.

Wu, C-Q, Oehlers, DJ & Glynn, C 1970, 'Layered analysis of resistance-deflection function of RC slabs retrofitted with FRP', STRUCTURAL CONDITION ASSESSMENT, MONITORING AND IMPROVEMENT, VOLS 1 AND 2, 2nd International Conference on Structural Condition Assessment, Monitoring and Improvement (SCAMI-2), SCIENCE PRESS BEIJING, Changsha, PEOPLES R CHINA, pp. 1170-1176.